New insights into bisphenols removal by nitrogen-rich nanocarbons: Synergistic effect between adsorption and oxidative degradation

In this work, nitrogen-rich graphene-like carbon sheets (N-GLCS) with high specific surface area (488.4 m(2)/g), narrow pore distribution and high N-doping (18.4 at%) were prepared and applied as both adsorbent and catalyst for the removal of bisphenols. Adsorption experiments demonstrated the high adsorption capacities of the N-GLCS toward bisphenol F (BPF) (222.9 mg/g), bisphenol A (BPA) (317.8 mg/g), and bisphenol C (BPC) (540.4 mg/g). Results showed that about 98.6% of BPA (70 mg/L) was removed at pH 7.0 within 80 min after the adsorption-catalytic degradation process. The N-GLCS also showed a superb reusability for the catalytic oxidative degradation of BPA (70 mg/L) with the removal percentage maintains over 83% after 5 cycles. With the synergistic combination of the excellent adsorption and catalytic properties of the N-GLCS, trace amount of pollutants can be preconcentrated and immobilized at the surface of N-GLCs, at the same time, active radicals were also produced at the surface of the N-GLCS by the activation of peroxydisulfate (PS), and finally the pollutants can be degraded in-situ by the active radicals. These findings provide a new avenue towards the efficient removal of trace-level EDCs from water solution by using the coupled adsorption-advanced oxidation processes. (C) 2017 Elsevier B.V. All rights reserved.